dasp1976. My habit is to turn on the pc, then mach3, then the contactor for the motors, then the key for the spindle. So, I think I am doing it as you indicate.

cropwell. The cables I use can be found her.e https://electroshops.ro/cabluri/cabluri-ecranate/liycy/, I used 3x0.75mm for limits, 4x1.5mm for motors, and 4x2.5mm for spindle all shielded. There is no soldering, just terminal blocks. No screw has come loose. I checked. I would consider the disconnect option, if it was not accompanied by a strage sound in motors, while the error occurs. Also, a cable would cause a persistent problem, in my humble opinion.

I think the relay that is clicking is the one that goes on in order to start the spindle. Here is what I did https://rawcnc.com/how-to-control-sp...other-inverter. My settings are the same with the only difference that I set the PWMBase Freq to 100 instead of 1000.

Finished another carving today, without any kind of problem., but I cannot trust this machine yet, and I am reluctant taking any large orders from customers as I am never sure what hapens next and if I can deliver in time.